County · code 55039
Fond du Lac CountyWisconsin
Fond du Lac County is a county in Wisconsin, with its seat in the city of Fond du Lac. The county was created on December 7, 1836.
- Founded1836
- County seatFond du Lac
- Land area720 sq mi + 46 sq mi water
- Population104,154 2020 Census
- Parcels mapped60,374 checked 15 October 2026
Where it is
Fond du Lac on the map of Wisconsin
Wisconsin has 72 counties and county equivalents, each with its own records office. Shapes with a page are links.
History
Formed in 1836 from Brown County and Marquette County
An old deed may name a county that no longer exists, or a boundary that has since moved.
Fond du Lac County was created by Wisconsin Territory on December 7, 1836, from Brown County and overlapping with Marquette County, a boundary dispute that remained unresolved for twelve years. The county was organized for government purposes in 1839 and gained and lost territory through the creation of neighboring counties including Winnebago and Calumet. On March 6, 1848, Fond du Lac County gained undisputed jurisdiction over the disputed area with Marquette County, resolving the boundary dispute that had begun in 1836.
- 1836Fond du Lac County created Fond du Lac created by Wisconsin Territory from Brown; Fond du Lac overlapped the eastern part of Marquette (Overlap Area 2), creating a dispute that was not settled until 6 March 1848. Fond du Lac not fully organized, attached to Brown "for judicial purposes." · Wis. Terr. Laws 1836, no. 28, secs. 9,14/pp. 93-94
- 1840Gained territory Fond du Lac gained from Calumet, lost to creation of Winnebago (including the northern part of Overlap Area 2 jointly claimed by Fond du Lac and Marquette). · Wis. Terr. Laws 1839-1840, no. 12, secs. 8-10/pp. 18-20; Wis. Terr. Laws 1841-1842, p. 74
- 1844Gained territory Fond du Lac gained from Calumet, Winnebago, and gained all of Non-County Area 3. Fond du Lac fully organized, detached from Brown. Calumet and Marquette detached from Brown, attached to Fond du Lac "for judicial purposes." · Wis. Terr. Laws 1843-1844, pp. 8-11
- 1848Gained territory Fond du Lac gained from Calumet and gained all of Non-County Area 4, lost to Winnebago. Fond du Lac also gained undisputed jurisdiction of the overlap area between Fond du Lac and Marquette (Overlap Area 2), ending dispute dating from 7 December 1836. Non-County Area 4 and Overlap Area 2 eliminated. · Wis. Terr. Laws 1848, pp. 79-80
- 1848Became part of Wisconsin Fond du Lac became a county in the state of Wisconsin. · U.S. Stat., vol. 9, ch. 89 [1846]/pp. 56-58, and ch. 50 [1848]/pp. 233-235; Van Zandt, 128, 130
Show all 11 changes
- 1836Fond du Lac County created Fond du Lac created by Wisconsin Territory from Brown; Fond du Lac overlapped the eastern part of Marquette (Overlap Area 2), creating a dispute that was not settled until 6 March 1848. Fond du Lac not fully organized, attached to Brown "for judicial purposes." · Wis. Terr. Laws 1836, no. 28, secs. 9,14/pp. 93-94
- 1839Changed Fond du Lac organized "for the purposes of county government;" Fond du Lac remained attached to Brown "for judicial purposes." · Wis. Terr. Laws 1838-1839, loc. acts, no. 56, secs. 5-6/p. 129
- 1840Gained territory Fond du Lac gained from Calumet, lost to creation of Winnebago (including the northern part of Overlap Area 2 jointly claimed by Fond du Lac and Marquette). · Wis. Terr. Laws 1839-1840, no. 12, secs. 8-10/pp. 18-20; Wis. Terr. Laws 1841-1842, p. 74
- 1844Gained territory Fond du Lac gained from Calumet, Winnebago, and gained all of Non-County Area 3. Fond du Lac fully organized, detached from Brown. Calumet and Marquette detached from Brown, attached to Fond du Lac "for judicial purposes." · Wis. Terr. Laws 1843-1844, pp. 8-11
- 1844
- 1848Changed Winnebago fully organized, detached from Fond du Lac. · Harney, 121; Wis. Terr. Laws 1847, reg. sess., p. 96
- 1848Gained territory Fond du Lac gained from Calumet and gained all of Non-County Area 4, lost to Winnebago. Fond du Lac also gained undisputed jurisdiction of the overlap area between Fond du Lac and Marquette (Overlap Area 2), ending dispute dating from 7 December 1836. Non-County Area 4 and Overlap Area 2 eliminated. · Wis. Terr. Laws 1848, pp. 79-80
- 1848Became part of Wisconsin Fond du Lac became a county in the state of Wisconsin. · U.S. Stat., vol. 9, ch. 89 [1846]/pp. 56-58, and ch. 50 [1848]/pp. 233-235; Van Zandt, 128, 130
- 1848
- 1850Changed Calumet fully organized, detached from Fond du Lac. · Wis. Laws 1850, ch. 84, secs. 1-2, 11/pp. 52-53; Wis. Laws 1852, ch. 278, sec. 1/p. 423
- 1859Changed Legislature authorized Green Lake to gain township 16 north, range 14 east from Fond du Lac, dependent on local referendum that failed (no change). · McKenna, I, 391; Wis. Laws 1859, gen., ch. 69, secs. 1-5/pp. 75-76
Land and parcels
What the maps cover in Fond du Lac
Who publishes each layer, how good it is, and when we last checked.
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Parcels Good enough
Lot lines and tax-map numbers for 60,374 parcels from Fond du Lac County. Drawn for tax purposes: usually within a few feet of a survey, but not a survey.
checked 15 October 2026 -
Address points Missing
No public address points layer found for Fond du Lac County yet.
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Buildings Reference
Roof outlines traced from aerial imagery from FEMA Response Geospatial Office with Oak Ridge National Laboratory (ORNL). Good for seeing what is on a lot; not accurate enough to set a fence from.
checked 18 October 2026
- Official
- from the office that keeps the record
- Good enough
- a reliable statewide or national copy
- Fallback
- a guide only; check the official record
- Missing
- nothing public found yet
People and land
Fond du Lac by the Census
Source: US Census Bureau, 2020 Census; US Census Bureau, 2020 Gazetteer Files. Not endorsed or certified by the Census Bureau.
Rules and offices
Fond du Lac County's official site
We have found the county's site but not its offices yet; start there.
County government
- County government
The official website of Fond du Lac County.
See your own lot on these maps
Open Fond du Lac County on Parcel Chart's free map and click your parcel. Save it with a free account; the full record of your place (site map, projects, documents) is Pro, in early access.
Questions
Common questions about Fond du Lac County
- When was Fond du Lac County founded?
- Fond du Lac County was founded in 1836, formed from Brown County and Marquette County.
- What is the county seat of Fond du Lac County?
- The county seat of Fond du Lac County is Fond du Lac.
- Is there an online parcel map for Fond du Lac County?
- Yes. Fond du Lac County publishes a parcel map of 60,374 parcels, rated good enough here. You can click any parcel on it in Parcel Chart's free map, no sign-in needed.
- Has Fond du Lac County's boundary or name changed?
- Fond du Lac County was created in 1836 from Brown County and Marquette County. Since then the Atlas of Historical County Boundaries records 9 later changes, chiefly involving Winnebago County, Calumet County and Marquette County.
- Is my lot in a flood zone?
- We do not have flood maps for Fond du Lac County yet. Look up the address on FEMA's Flood Map Service Center, which shows the effective flood map for any lot.
Nearby